text: // Copyright 2021 Google LLC
  //
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  //
  //      http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  
  
  'use strict';
  
  function main(name, scope) {
    // [START iamcredentials_v1_generated_IAMCredentials_GenerateAccessToken_async]
    /**
     * TODO(developer): Uncomment these variables before running the sample.
     */
    /**
     *  Required. The resource name of the service account for which the credentials
     *  are requested, in the following format:
     *  `projects/-/serviceAccounts/{ACCOUNT_EMAIL_OR_UNIQUEID}`. The `-` wildcard
     *  character is required; replacing it with a project ID is invalid.
     */
    // const name = 'abc123'
    /**
     *  The sequence of service accounts in a delegation chain. Each service
     *  account must be granted the `roles/iam.serviceAccountTokenCreator` role
     *  on its next service account in the chain. The last service account in the
     *  chain must be granted the `roles/iam.serviceAccountTokenCreator` role
     *  on the service account that is specified in the `name` field of the
     *  request.
     *  The delegates must have the following format:
     *  `projects/-/serviceAccounts/{ACCOUNT_EMAIL_OR_UNIQUEID}`. The `-` wildcard
     *  character is required; replacing it with a project ID is invalid.
     */
    // const delegates = 'abc123'
    /**
     *  Required. Code to identify the scopes to be included in the OAuth 2.0 access token.
     *  See https://developers.google.com/identity/protocols/googlescopes for more
     *  information.
     *  At least one value required.
     */
    // const scope = 'abc123'
    /**
     *  The desired lifetime duration of the access token in seconds.
     *  Must be set to a value less than or equal to 3600 (1 hour). If a value is
     *  not specified, the token's lifetime will be set to a default value of one
     *  hour.
     */
    // const lifetime = ''
  
    // Imports the Credentials library
    const {IAMCredentialsClient} = require('@google-cloud/iam-credentials').v1;
  
    // Instantiates a client
    const credentialsClient = new IAMCredentialsClient();
  
    async function generateAccessToken() {
      // Construct request
      const request = {
        name,
        scope,
      };
  
      // Run request
      const response = await credentialsClient.generateAccessToken(request);
      console.log(response);
    }
  
    generateAccessToken();
    // [END iamcredentials_v1_generated_IAMCredentials_GenerateAccessToken_async]
  }
  
  process.on('unhandledRejection', err => {
    console.error(err.message);
    process.exitCode = 1;
  });
  main(...process.argv.slice(2));
  